The code is built around the data assumptions in [1]}, who use nine age groups, 0-9, 10-19, 20-29, 30-39, 40-49, 50-59, 60-69, 70-79, and 80+. The probabilities of hospitalization and critical care need for these age groups are estimated by Verity et al. [2]}. The population numbers for these age groups come from the Statista web site (https://www.statista.com/topics/755/uk/). The number of critical care beds in England at the end of 2019 was around 4100, with around 11000 more planned at the emergency Nightingale hospitals, so as an optimistic figure we took 12500 to be the number. The mean infectious period was taken to be 7 days, in line with values in [1]}, but it seems this can be highly variable. Various values were tried for \(p\) , the probability of an infected person being symptomatic, but the baseline for this parameter was 0.3. Infectivity was taken to be 2.4, in line with values proposed by [1]}, but again there appears to be quite a wide range of possible values, as we see from [5]}. The contact matrix values \(m^O\) , \(m^H\)  are derived from [6]}; they work with different age ranges, so some pre-processing of their data had to be done; the code for this is available from the author on request.
